Asymmetric organic synthesis. Preparation and Birch reduction-alkylation of 2-methyl-3,4-dihydroisoquinolin-1-ones

Article abstract of DOI:10.1016/0040-4039(95)00819-X

Birch reductions of 2-methyl-3,4-dihydroisoquinolin-1-ones 1 and 6 generate enolates 2a and 2b and alkylations provide 1,4-cyclohexadienes 3a-3e and 7a-7c. The synthesis of a racemic structural analogue, 9, of the potent analgetic levorphanol is described.